Unit heater



'- Aug..25, 1931. c. c. CARSON UNIT HEATER Filed No'v. 25, 1929 y 2 She'ets-Sheet l INVENTOR Cardan BY/ @W @u ATTQRNEYS Patented' Aug. z5, i931' 1 UNITED lsTA'rls'. s

' curroan c. ourson,- or cmcaeqmmoxs Um'r HEATER Appuegan'ma november as, im. serial no. 409,051.

' AThis iwe'ntion relates-:m industrial una' heaters of the t used for heating lar e buildings, auditoriums, theatres or the wol` ing areas in large.- factories and the hke. Among other objects, it aims to provide an. improved relative] simple, compact and eicient heater having provision for relcirculating and heating-room air and for 'admitting Ventilating air tothe heater. lo This-application involveswertain impor- 1 tant improvements on unit heaters of the same general ty as those disclosed in my o o-pending app ications, Ser. No. 308,681

tiled Sept. 27, 1928 and Ser. No. 398,443-` 4 A Yclrculate air 1nthe building through the mf filed Oct. 9, 1929..

` In the accompanying drawings:

1 isy a side elevation o f a suspension unit eater embodying the improvements;

v Fig. 2 is al1-elevation on a reduced scale showing the arrangement of one unit in a factory building;

Fig. 3 is a longitudinal sectional view of the heater; and l ,Fig. 4 is a top plan view.

buildings, the conservation ofloor space is a greatV desideratum because of the expense of construction and maintenance.. In many instances indirect air heaters are vsuspended :o above the floors or mounted on columns, beams and the like so as not to occupy. any floor space available for the placement of machinery, etc'. But the suspended heaters 5now infgenesalfuse arecnot as''eicient as .theyy should be because an unduly large reentage of the h ot air delivered by t em rises; above the working ace orthe zoneto be heated and the heat 1s lost in the roof zone where it is dissipated b radiation and conduction as well as by co dlar'cnrrents. This invention, therefore, ailsto. rovide a highly eilicient anidfsimple unit eater of this type having provision to insure` proper distribution ofthe heated air in thejzone or spaeeto be heated-'and to confine it to. a-large extent to that z one.

Referring particularly tothe drawings wherein the invention-'is embodied in a so#Y called suspension unit heater, there isshown 5 0 a sheet metal'casing ,having in1et con In modern shops,` factories and -large' i charged from the casing by Ythe fan.

duits or ducts 11 and 12 and a main outlet conduit or discharge duct 13 which is preferably rectangular in cross section. In this example, the casing is substantially T-shaped and the inlet duct 11 is arranged to admit outside air or air from another room, bei shown as supported in an opening in a wa of a building 14. The other inlet duct 12 is here shown as extending downwardly to a point above the working area or s ace to be eated. Conveniently, the duct12 asatelescoping section 15 so that its height aboye the floor ofthe building may be adjusted. As will be seenv in Fig. 2, the idea is to re takegduct 12 and also to admit a controlled amount of fresh air from the exterior or from another room, as the case may be. The

outlet end of'the casing is herev shown as bein vsuspended from a ceili by means of 7 suitsile suspensioin bars or rgs `16 althougl it will be understood that the casing ma supported vvon columns, beams or the e,` 'depending upon the available supporting structures in a building or large room to be u heated. y A

v 'Within the casing 10 there is shown an air blower-17 which in.v this instance is an4 g ordinary propeller type fan to which is directly connected Van electric motor 18. The arrangement is such that the fan sucks air through the intake ducts and discharges it through the casing into the space to be heated.- Ihisrfan'is suitably mounted within a ring 19 secured tothe inside wall of the casing. v l

Adjacent to the discharge nd of the duct 13 and in front of the fan the is shown a heat exchanger conveniently composed of a series of' tubes 20.v connected at their upper g,

and I ower ends to headers 21, the design .being substantially the same as those now in common use. However, the upper header 21 is spaced a substantial distance from the up rrwall of the casingfor a purpose later gg tobg described. Ordinarily, steam/.or other heat exchanging fluid is circulated through the leat exchanger so as to heat the air blown between vthe pipes or tubes and dis- 55. ofthe discharged cold air stratum.

' shown a plurality of louvres 22 in front of the heat exchanger and they are arranged to As is usual in some unit heaters, there is be'adjusted by means of a suitable rod or bar 23 adapted to be raised and lowered in a guide 24 and' clamped in adjusted position, preferably by an ordinary wing nut. The idea of adjusting the louvres isto deiect the. heated air at diii'erent angles into the space or zone to' be heated.

In accordance with the present invention, apart of the air delivered through the casing by the fan or blower element is utilized to create a relatively cold and relatively high velocity stratum or curtain for confinin the heated air and causing it to circu ate within the working area or space. In my aforesaid co-pending applications, there is disclosed the broad idea of' discharging substantially horizontal strata of relatively cold, high velocity air above strata of heated air. In the present instance, it is desir'- able to be able not only to regulate the vthickness and velocity as well as the temperature of the discharging kcold air stratum, but also to control the angleat which the stratum is discharged so as to confine the heat*- ed air within the desired working range, de-

pending upon the height of the unit above the floor, the width of the building or room in which the unit is located and several other factors. Accordingly, there is shown a pair of adjustable and curvedplate members 2,5 pivoted at .their opposite ends andk their rear edges between the sidewalls of the rectangular outlet duct 13 and arranged to be adjusted either independently or in unison. In this example, Vthe shape and arrangement of the plates are lsuch as to provide a sub stanti'ally Venturi-shaped nozzle in cross section. These' plates may be; adjusted by various means, but herein there is shown an articulated rod 26 on one side of the casing connected to a pair of pivoted arms 27 and 28 having curved slots 29 within which fixed arms 30 on the shafts'of the plates are adjustablyv clamped by `means of wing nuts 31 (Fig. 1). The articulated rodis adapted to be clamped in adjusted positions in a suitable clamping gulde 32. rangement of the adjusting mechanism, it will be seen that the nozzle may be made to discharge at dili'erent angles and the width may be varied in order to vary the thickness To prevent any of the relatively cold air from escaping below'the lower nozzle plate 25 and creating eddy currents, there is vshown a fixed baille member 33 arranged between the upper header 21 and the pivoted rear edge of said late. Thus, all of the air delivered by the an'must'pass through the nozzle 4and through'the heat exchanger.

'- Itis further desirable that the relative volume and, consequently, the relative' veloc- By the ar- `velocities between the hot and cold air strata which will produce the best rresults and preventl eddycurrents of heated air from commingling with the cold stratum. In this example, there is shown a deiector plate 34 solnewhat like an ordinary damper pivoted at its reareedge adjacent to the rear edge of the lower nozzle plate 25. This deector is adapted to be adjusted by any suitable means but, in this instance, there is shown an arm 35 adapted to be clamped in yangularly adjusted positions by means of an ordinary wing nut 36, this being one of the simplestand most convenient forms of adjusting means. ered a relatively large volume of air is discharged through thenozzle at a higher pressure and velocity.' Consequently, the volume and velocity of air passing through the heat exchanger will be diminished.

To enable the stratum of cold air to be deflected, at different angles after it is discharged from'the cold air nozzle, there is shown a pivoted baille member 37 above the ample, the pivoted edge of the baille has an integral slotted arm 38 adapted tobe held in angularly adjusted position by means ofv a wing nut 39 in much the same fashion .as thedeliector plate 34. By utilizing this baille to deflect the discharging stratum of cold air, the angle of discharge can be varied to a greater extent than is possible by adi Vjusting the two nozzle plates 25, because of the limited range of adjustment of said plates. that the two strata'of air be discharged at a lslight angle to each other and when the louvres for the hot air are'adjusted, lit is a relatively simple matter to change the adjustment of the baille 377' accordingly without disturbing the nozzle plates. j

The relativequantities- 'of fresh air and recirculating air admitted through the in-v take 4ducts 11 and 12 are adapted tobe controlled by ordinary dampers 40 and 41 connected .and arranged to be operated in unlison s o as to admit a definite quantity ofair for all adjustment. In this example, both dampers have operating arms 42 at one side of the casing connected to an articulated adjusting bar 43 adapted to be clamped in fdif ferent adjusted positions byrmeans 'of a vsuitable clamping guide '44. '3" f It is desirable, in manyl instances,

combination, the air pre-heater is utilized in conjunctionwith the adjustable deflector plate 34 so as to maintain a practically constant `temperature differential between the cold air stratumand the heated air when there are variations in the temperature of Ventilating air admitted through the cold air intake duct.

' In the operation ofthe heater, it willbe seen that theh'eated air, which always had a tendencyto rise to the roof of the building,

is confined very largely to circulate below the stratum or curtain of cold air, `while the stratum of cold air which tends to fall' to the floor, counteracts to some extent the, ten'- dency to rise. The curtain of cold air which travels at a higher velocity than the heated air, is practically impenetrable except by the eddy currents vprobably set up between the strata. The recirculating intake duct 12 of' the heater sucksv in the -air from above the vworking area and ,sets up a continuous circulation of thehot air from'the heater down# wardly across the building and back into the intake duct so that it does not escape into the upper zone or area vof the building and radiate to the exterior.

, 'Itis contemplated that very few adjustment'45; the thic ments of the vparts will be-necessary or even desirable after the installation is put in operation and the desired or most etiici'ent temperatures, velocities, volumes, thicknesses, directions and. relative heights or an' gles ofthe strata are established empirically. The temperature` ofthe cold air stratlun 1s regulated to a lar extent by the heater eleess -by means of the nozzle plates 25; the velocit by means of the deflector plate 34';the 'rection by means of the nozzle platesl 25 adjusted in unison and also by the ivoted baille 37 .n Moreover, the height'o the cold air stratum may be varied with respect tothe discharging hot air stratum or stream by means of the nozzle plates 25 independently of the pivoted` balile 37.`

While the improvements are shown asbeing embodied in asuspension unit heater, it

y is apparent that many ofthe important features of the-invention are equally applicable tovfloorf--heaters such as are shown 1n my aforesaid co-pending applications. Consequently, the claims are not all limited to a suspensionv type ofv heater).

Obviously,- the present vinvention is not restricted to the particular embodiment therel of herein shown and described. Moreover,

' itis not indispensable that all the features o f' theinvention be.,k conjointly, since Vtheyf-'may be 'employed advantageously in various combinations and sub-combinations.

What I claim is I 1. A unit heater of the character described comprising, in combination, a casing having exchanger to adjust the angle of discharge' of the heated air; and a nozzle arranged above Athe louvres for delivering a part of the air discharged by said fan above the discharging heated air-without permitting such air to be raised in temperature by the heat exchan r.

2. A unit eater ot the character described comprising, in combination, a casing having inlet and outlet openings; a fan within the casing; a heating element in front of the fan; means for varyin the direction of discharge of heated air t erefrommeans for discharging a ortion of the air delivered by the fan in a re atively high velocity stratum above the heated air; and means for suspending said heater above the floor of the room or'spaee to be heated.

v 3. A unit heater khaving provision for heating and'fventilating a '--working space within a building eoinprisi in combination, acasing having an air ischarge opening; a fan within the casing; a heating element lwithin the casin adjacent to the discharge opening; an a justable nozzle above scribed comprising, in combination, a cas,

ing having a discharge outlet opening; a fan wlthin the casing; a heatingl element arranged in front ofthe fam-means for bypassing a portion of the air from the fan I* around the heater element whereby to createV a'stra'tum of relatively cold air above the dischargin heated air; an intake duct connected to t e casing at the intake side of the fan and extending through a wall of the room in which vthe heater is located whereby to draw Ventilating air into the rooml through the heater.

having an air inlet conduit and a substantially horizontal outlet conduit; heat exchanging'means within the casing; a nozzle in the outlet end of the casing to discharge 5. A unit heater of the character de' scribed comprising, in combination, a casing aportionof the air in a thin stratum above .the heated air discharged from the' heater without passing said air through the heat exchanger; and means for adjusting the nozzle to regulate theY thickness of the cold air stratum.

6? A unit heater of the character described comprising, in combination, a casing; `a 'heat xelement without raising its temperature whereby toA create a cold air stratum above the dischargin hot,v air; an intake ductfor admitting outslde air to the casing; an adjustable'intake duct for re-circulating' the room airv through the\heater and yextending below` -the level thereof; and means for regulating the proportion of airdelivered tothe casin by each of said ducts.

7 unit heater of the character described comprising, in combination, a casin having a pair of intake conduits and a ischarge conduit; a heater element Iwithin the casin a fan arranged to draw air from sai'd inta e ducts and discharge it through said heater element; means for discharging va stratum of relatively cold air above .said heater element so as to confine the heated air to the workin space in the room to be heated; means or regulating the quantity and veloc' ity of the'air inlsaid ,cold air stratum; and means to control the admission of air through -said intake ducts, one of said ducts being connected to deliver f resh air tothe heater and the other extending downwardly below the heater casing to re-circulate room air through the heater.

8. In a unit heaterand ventilator of thecharacter described, acasing havin'g air inf let and outlet conduits; a fan@ within the casing; a heating element in front of the fan; means for controllingthe discharging heated air from the heating element into a room to be heated; means for discharging a` portion of the lair delivered by the fan in a stratum above the heatedair; and means for regulating the cold air strata so as to.

-control'the temperature, thickness, velocity,

direction and height of said strata.

' 2 9. A unit heater and ventilator ofthe character described, comprising, in combination, a sheet metal casing presenting top, bottom and side walls and having an 'air outlet conduit ;""a propeller fan in said casing; a heat transferring element in the front portion` of the casin said heat transferring element leavinga-k ree opening above it so as to permit air toiiow in a stratum through,A

- the openingwithout being heated `and 'at' a velocity slightly ,higher rthan the heated air issuing from the heaterelement; a series of adjustable .louvres to. direct the heated air issuing from said heater ,element a a? duct ofair; a duct extendingldownwardly from the casing so as to re-circulate the air withinthe space to be heated through the heater;

means forregulating the proportion of ai'r admitted through each ofthe ducts to the fan; fand meansfor suspending theheater casing above the floor of the space or room to be heated. l

10. A suspension heater of the character described comprising, in combination, a casing suspended above the area to be heated and having inlet and outlet openings; a fan within the casing; a heater element adjacent to the outlet opening of the casing; means to deliect the heated air downwardly at an angle from the outlet opening; a pair of pivoted nozzle plates arranged in the ulpper portion of the outlet openingv above t e heater element to discharge'a relatively thin.

stratum of cold air at a relatively high -velocity above the heated air stratum; means to adjust the nozzle plates so as to vary the thickness of the cold air stratum; means tovary the angle of discharge of the cold air stratum from said nozzles; and means to regulate the relative volumes, temperatures and velocities of the discharging stratum.

11. In a unit heater of the character described, a' casingv adapted to be suspended anismfor-adjusting the plates in unison.;

and a pivoted 'deilector plate behind 'said nozzle to regulate the quantity, pressure and velocit ofthe air issuing from said nozzle.

12. n a suspension unit heater .of the character described, a casing having an inlet duct and anq'outlet duct; a fan within the casing; aheat'er element arranged in front of the fan adjacent to the outlet duct; ad vjustable louvres for discharging tlie .air downwardly at 'an angle from the outlet end of the casing; a pair ofpivoted and adjustable nozzle plates arranged above the heater element so as to by-pass and discharge 'a relatively cold stratum of air above the heated air to confine it within the space to beheated; an adjustable delector plate be hind the nozzle to vary the volume, pressure and velocity ofthe air discharged through saidwnozzle; means to-vary the angle of discharge of the nozzle; means to regulate the thickness of said cold air stratum; and a e! connecting said casing with an outside source fpivoted ballie arranged front of the nozzle l to vary the angle of discharge of the issuing stratum.

13. In a unit heater of the character described, a casing having inlet and outlet openings; a fan connected to discharge air througlrthel outlet opening; a heater within the casing through which a .portion of the air passes; an' adjustable nozzle within the casing arranged to discharge a relatively thin stratum of relatively cold air above the issuing streamof heated air to confine it to the area to be heated; and means to deflect the issuing stratum of relatively cold air so as to vary the angle of discharge with respect to the stream of heated air.

14. lA suspension unit heat-er having means to discharge heated air downwardly at an angle into the space .to be heated; and an angularly adjustable nozzle associated with the heater and arran ed to discharge a Wide thin stratum of relatlvely cold air above the stream of heated air to confine it to said space.v

15. A suspension heater of the character described comprising, in combination, a casing having a substantially horizontal air outlet duct; an air inlet duct associated with the casing; a heat exchanger including a plurality of vertically disposed tubular e1e' ments arranged in said air outlet duct; a fan within the casing behind said heat exchanger; al1 adjustable nozzle within the outlet duct above the heat exchanger arranged to discharge a thin, relatively Wide stream of air delivered by the fan; and means to direct the heated air and the stream of air from said nozzle at different angles of inclination'with respect to the horizontal 'and with res ect to each other.v

i u testimony that I claim the foregoing as my own, I have hereto aliixed my signature.

CLIFFORD c. CARSON. 

